I asked the same question from my biology teacher. He said, the mitochondrial ribosomes, the chloroplast ribosomes & the bacterial ribosomes are so similar that if you (For example) take the little subunit of ribosome from mitochondria & the large subunit from chloroplast & give it to a bacteria it will be able to produce protein

Well, that's a little bit other question The point you are asking now is, whether the homologous sequences are similar enough to be able to complement each other.I was answering, whether the complete chromosomes are similar.

Both posts are correct. (Althrough, I think, that not whole ribosome is coded by mitochondrion/plastid). My point is, that plastids and mitochondrion are coding for different proteins (e.g. photosynthesis aparathus in chloroplast × Calvin cycle enzymes in mitochondrion) and also the dependence of these organels on nuclear gene transcription is various in different organisms (there was some picture in Alberts' Cell Biology regarding, what genes are coding chromosomes in (mitochondria/plastids?) of different species)